Periodization discussion

We started a project with pro soccer players on their way to re-join the team after an injury a couple of years ago. It implied the use of very short training workouts (16-20 minutes total allocated time) with the aim of getting them ready to work with the rest of the team and be back on the field in the shortest time possible after rehab. Workouts were assigned daily,sometimes as doubles,most of the time as singles,and were done every day with no day off until the first full time match were successfully played. Of the total 16-20 minutes the only factor we kept purposefully constant by design was the total time allocated for recovery (15-out of 16 to 20- minutes).
Players were monitored and functionally evaluated in a number of areas,ranging from pure task performance to general physiological indicators. The results were so encouraging in all areas (display of performance capabilities,general and specific fitness to mention a few) that we decided to export the very same training format to athletes outside the team,and of different sport specializations, and eventually to private PT clients and even patients from all endeavours. All with rather consistent extremely positive results over time.